Thanks for sharing all this great info.
I'm having this issue. Tried different mag components. (Gram & mbx followers, henning +4 base pads, mecgar tubes, gram springs, even bought one of the new mbx mags 23/24 rd mag), different bullet profile, different OAL. Running 15lb commander with w74 guide rod but it's nose dived enough and really stuck in there. I don't think it would matter how heavy of recoil spring you had. Usually happens on a fuller mag but doesn't have to be completely full, even happens on half full sometimes Any ideas? Pulling my hair. It's to the point where i can't shoot it at a match anymore.